Rosin is the sap from pine tree. It is a sticky substance but can be processed and used for:
- Rosin is commonly used as a flux in metallurgy, especially for soldering.
- Bowss for musical instruments such as the violin are normally rubbed with rosin to increase the grip on the strings.
- It can also be used to demonstrate resonance in aluminium bars by stroking them with rosin tipped fingers.
- Ballet slippers are rubbed in powdered rosin to reduce slipping.
- Baseball pitchers use a rosin bag to keep their hands dry. Usage of rosin is specifically mentioned in major league baseball rules